Singh, Jitendra Pal Kim, So Hee Won, Sung Ok Lim, Weon Cheol Lee, Ik-Jae Chae, Keun Hwa 2024-01-20T04:33:07Z 2024-01-20T04:33:07Z 2021-09-03 2016-04 1466-8033 https://pubs.kist.re.kr/handle/201004/124253 In the present work, Fe valence state, covalency effects, and metal-oxygen hybridization are discussed for ZnFe2O4 using X-ray absorption spectroscopy. A few sets of nano-sized and micro-sized zinc ferrite were synthesized using the nitrate method. Nanoparticles of ZnFe2O4 were synthesized by heating precursor at 300, 400, 500, 800, 1000, and 1200 degrees C for 1 h. To synthesize micro-sized ZnFe2O4, the obtained nano-particles were annealed at 1200 degrees C for 12 h (bulk treatment). X-ray diffraction shows the presence of cubic spinel phase in nano-sized as well as micro-sized ZnFe2O4. Scanning electron microscopy measurements show that particle size ranges are 40-80 nm and 1-2 mu m for nano-sized and micro-sized ZnFe2O4, respectively. Fe L-edge spectra of these materials envisage the presence of spectral features corresponding to t(2g) and e(g) symmetry states created due to Fe(2p(3/2))-Fe(3d) and Fe(2p(1/2))-Fe(3d) in octahedral crystal field. This reflects the presence of Fe3+ states in nano-sized and micro-sized ZnFe2O4. eg states dominate in micro-sized ZnFe2O4. O K-edge spectra for these materials can be distinguished by pre-edge and post-edge regions. Pre-edge and post-edge regions are associated with O(2p)-Fe(3d) and O(2p)-Fe(4s,4p) hybridized states. The extent of hybridization estimated from the intensity ratio of O(2p)-Fe(3d) and O(2p)-Fe(4s, 4p) hybridized states is higher in nano-sized ZnFe2O4. English ROYAL SOC CHEMISTRY X-RAY-ABSORPTION ZINC FERRITE NANOPARTICLES TRANSITION-METAL ELECTRONIC-STRUCTURE FACILE SYNTHESIS SPINEL-GRAPHENE GRAIN-SIZE TEMPERATURE OXIDE ZN Covalency, hybridization and valence state effects in nano- and micro-sized ZnFe2O4 Article 10.1039/c5ce02461g 1 CRYSTENGCOMM, v.18, no.15, pp.2701 - 2711 CRYSTENGCOMM 18 15 2701 2711 scie scopus 000374046800013 2-s2.0-84964440155 Chemistry, Multidisciplinary Crystallography Chemistry Crystallography Article X-RAY-ABSORPTION ZINC FERRITE NANOPARTICLES TRANSITION-METAL ELECTRONIC-STRUCTURE FACILE SYNTHESIS SPINEL-GRAPHENE GRAIN-SIZE TEMPERATURE OXIDE ZN Covalency hybridization and valence state ZnFe2O4